1. Field of the Invention
The present invention has been made in view of the above problem in the prior art. It is therefore an object of the present invention to provide an ink jet head maintenance mechanism which does not involve ink dropout even when an ink of the above-described nature is used and the ink jet head is left unused for a long period of time, making it possible to perform satisfactory printing.
2. Description of the Related Art
In a conventional ink jet head maintenance mechanism, a nozzle surface of the ink jet head is capped in order to restrain drying of the nozzle surface after completion of printing. When the ink jet head has been in a standby condition for a long period of time or when the ink jet head has been left unused for a long period of time with the power source off, a cleaning operation according to the standby time is performed to clean the nozzle surface and the interior of the nozzle when starting printing again.
However, in an ink jet printer using a quick-drying ink a solvent of which is an organic solvent or the like, even if the nozzle surface of the ink jet head is capped for protection, a very small quantity of ink around the nozzles is dried when the ink jet head is kept in a standby condition for a long period time or it is left unused for a long time with the power source off. According to that, pigment, a resin layer, etc. adhere to the interior and periphery of the nozzles, and then some of the nozzles will be left clogged even after cleaning is performed, resulting in a problem of a so-called defective discharge in which ink cannot be discharged at the time of printing.